Field of Invention
The present invention relates to a wireless power transfer system having positioning function, and a positioning device and a positioning method therefor; particularly, it relates to such a wireless power transfer system which is capable of locating the most efficient power transfer position, and a positioning device and a positioning method therefor.
Description of Related Art
Conventionally, in a wireless charging system, there are two approaches to align a transmission coil of a power transmission side with a receiving coil of a power receiving side. The first prior art approach is shown in FIG. 1. An identifiable mark 13 is provided on a charger plate 14. Ideally, such identifiable mark 13 is located above the center of the transmission coil 12 of the power transmission side. However, during assembly, this identifiable mark 13 may not be precisely aligned to the center of the transmission coil 12. Besides, usually, the location of the receiving coil of the power receiving side (e.g., a portable electronic device) is not provided with any mark, so it is difficult for a user to align the transmission coil with the receiving coil by this prior art approach.
In the second prior art approach, a magnet is added at the power transmission side, for attracting a ferromagnetism material provided at the power receiving side. However, the effect of this approach is limited when the power receiving side has a significant size and weight. In addition, the magnet may cause an interference to the power receiving side.
In view of the above, to overcome the drawbacks in the prior art approaches, the present invention proposes a wireless power transfer system, and a positioning device and a positioning method therefor, which are capable of locating the most efficient power transfer position.